You have to combine Ashley and Lauren's servings to find the remainder for cole. To do that, you need a common denominator for the two fractions. 1/6 can be multiplied by 2 to get 2/12. Now you can add 7/12 and 2/12. You get 9/12. 12/12 - 9/12 is 3/12. When simplified the answer is 1/4!
I assume you mean 7/12 and 1/6. Add 7/12 and 1/6 to find the total amount eaten by Ashley and Lauren: 7/12 + 1/6 = 7/12 + 2/12 = 9/12 = 3/4 Ashley and Lauren ate 3/4 of the tub. Cole ate the rest. 1 - 3/4 = 4/4 - 3/4 = 1/4 Cole ate 1/4 of the tub.
